Coil wrapping machine



Nov. 29, 1960 L. E. FOLEY, JR., ETAL COIL WRAPPING MACHINE Filed Feb. 1, 1957 4 Sheets-Sheet 1 fha/entorseroy E.' FZ7/oy, JZ? Robert A. Watson, by 7/,44-1/ Tho/r Attorney Nov. 29, 1960 L. E. FOLEY, JR., ErAL 2,962,236

con. WRAPPING MACHINE Filed Feb. 1, 1957 4 sheets-sheet 2 90 [3v/f4 The/'r Attorney.

Nov. 29, 1960 L.. E. FOLEY, JR., ETAL COIL WRAPPING MACHINE 4 Sheets-Sheet 3 Filed Feb. 1, 1957 n, W5 W M M yt ,Mor e M m Nov. 29, 1960 L. E. FOLEY, JR., ErAL 2,962,236

COIL WRAPPING MACHINE Filed Feb. 1, 1957 4 Sheets-Sheet 4 fhyenoms:

Lef-oy E Fo/ey, JIT;

-electric strength at the joint where overlap occurs.

United States Patent() coIL WRAPPING MACHINE Leroy E. Foley, Jr., Schenectady, and Robert R. Watson,

Ballston Spa, N.Y., assignors to General Electric Company, a corporation of New York Filed Feb. 1, 1957, Ser. No. 637,733

6 Claims. (Cl, 242-6),

ever, since the insulation resists taking new shapes and must be. applied in very thin layers, particularly whe-n a coil is wrapped by hand. it is possible to-obtain well insulated coils by employingI hand wrapping methods, but the resultant product is expensive because of the undue amount of labor involved'in themanufacturing process er than usual in order to account for the decreasel in di- The thicker layers of material thus used require'larger'slotvv dimensions which increases the physical size andrcost of the machine.

rCoil wrapping machines are currently usedfor wrapping coils withv strips of insulating material having strip widths approximating two inches but` considerable manualdexterity is required by the operator sincev the c oil is moved relative to the strip of material. Further, it is obvious that the size of coil susceptiblevoff being wrappedinthis manner is limited because of weight and size considerations thereby precludingthe wrapping of coils for large machines by a single operator. Hot wrappingmachines have been-used to wrap-sheets of greater width but shrinkage of the insulation resulting from application of heat occurs during the wrapping process so that full advantage cannot be taken of the shrinkage characteristics. Also, considerable skill is requiredbythe operator since the coil-l must be moved relative to moving parts in the machine which further increases the probability of inadequate wrapping. In view of the fact that the exposed parts of the machine are operatedv at temperatures in the neighborhood of l-50 C., the operator must exercise care to prevent being burned which also increases the wrapping time forv any particular coil.

Accordingly, an object of our invention is to eliminate the above-described disadvantages now inherent in the prior art machines by providing a new machine capable of speedily wrapping the slot portions of a coil without rea quiringy a high degree of skillon the part of an operator.

Anotherobject of the invention is to provide amachine .l capable of handling thick layers of material while simultaneously obtaining av tight wrapduring the wrapping process so as to produce al better insulated coil on a more ecot nomical basis.

In carrying out the above-described objects ofk our invention, we-provide a machinehaving a pair. o f platents automatically actuated" toanopenfor closedV position for receivingv a coil and insulating material,l adapted for posi- .and moreover, the build of insulation must be made thick- A rotation therein.

tioning therein. The platents, when closed against the coil and material, rotate around the coil and in so doing, wrap they material on the coil while the latter is loosely held against movement by the operator. Selective rotary movement of the platens is obtained by a motor having a clutch and brake interposed therebetween while the number of revolutions made by the platens and their stopping position is controlled by an electrical circuit having a counter and time delay elements incorporated therein. In order to simplify the wrapping process, the machine and associated air and electrical circuits are arranged in a manner requiring an operator only to set an indicator for the number of turns of material desired on a coil and to actuate a foot switch to initiate operation of the machine after a coil is placed therein for wrapping.

While the specification concludes with claims particularlyl pointing out and distinctly claiming the subject matter which we regard as our invention, it is believed the invention will be better understood fromthe following description taken in connection with the accompanying drawings in which:

Figure l is a front View in elevation illustrating the coil wrapping machine placed on a table with the motor and associated control equipment vlocated therebeneath;

Figure 2 is aside View in elevation of the machine supported on the table shown in Figure 1;

Figure 3 is a View taken on lines 3-3 of Figure l; Figure 4 is a View taken on lines 4-4 of Figure 3*; Figure 5 is a perspective view of the machine showing a coil' and a sheet of insulating material placed in the platens immediately prior to wrapping the insulation on the coil;

Figures 6 through 9 showy the various positions assumed .by the platents with respect to the coil during the lirst quarter turn of the wrapping process; and

Figure lOdiagrammatically illustrates the air and electrical circuits used in controlling the machine shown in the preceding figures.

Referringnow to the drawings wherein like reference characters designate like or corresponding parts throughout the several views, there is shown in Figure 1, a table 20-supporting left and right-hand assemblies or frames 22 and 24 arranged for providing rotary movement to a pair of rotatably mounted platents 26 and 28 positioned therebetween. Located below the table is a motor and other associated equipment for driving the platens as more fully described hereinafter.

The left-hand assembly 22 serves only to support the platents and equipment necessary to obtain actuation between open and closed positions, but in order to accommodate platens of various sizes to permit wrapping coils of different lengths, the left-hand assembly is adjustably' mounted in grooves and channels 30 formed in the uppersurface of the table. The assembly is mounted for movement to the right or left as shown, and is held in a xed position after adjustment by a nut and bolt arrangement 32 or similar securing means.

Referring more specically now to Figures 1 through 4, many parts of the left and right-hand assemblies `are identical and respectively consist of end plates 34 extending upwardly from a base 36 and are provided with opposed circular openings 38 provided near the upper end. A stationary journal comprising members 4t) and .42 (enlarged view in Figure 4) is permanently xed in the openings by screws 44 attached in the outer surface of end plates 34. The outer peripheral surface of fixed journal members 40 and 42 coact to form a V which receives arbor 46 having a mating surface 48 adapted for In order to impart motion to the arbor, a sprocket wheel 50 having teeth 52 is rigidly attached thereto by screws 54 which also serve to anchor drive plates 56 to the arbor 46. Platens 26 and 28 are then fastened between the drive plates 56 by bolts 58. Rotary movement of the platens is thereby achieved by driving the sprocket wheel which in turn transmits force to the drive plates 56 by virtue by the screw connection 54 between the parts. As previously indicated, the arbor 46 which is also connected to the sprocket wheel, rides in the bearing surface provided by the journal :'members 40 and 42. In order to account for variances in these bearing surfaces due to manufacturing tolerances and wear of the parts, the journal members can be adjusted axially of the machine by screws 60 arranged in a manner to successively urge the journal members apart while the next draws them together.

The structure of the front and back platens 26 and 28 is more clearly shown in Figure 3. These elements are automatically opened and closed with respect to each other and are designed to rotate around the coil while simultaneously wrapping the insulation thereon. As shown, each platen is U-shaped in construction and is moved respectively to the right and left as shown in Figure 3. They are movably mounted on bars 70 attached at each end to the drive plates 56 and are guided in their movement by pins 72 secured to the bars and extending into slots 74 provided in the upper and lower surfaces of the platens. The bars are of relatively soft material and subject to wear by the continued movement of platens thereon, but this undesirable feature is eliminated by utilizing steel or other hard surface inserts 76 attached to the bars by screws 78. The platens therefore have a small contact or wear surface as shown in Figure 1.

In order to provide a biasing force acting to urge the platens toward each other, springs 80 are enclosed therewithin and bear at one end against the inner ends 82 of the platens and at their other ends against a stop member 84 held in position by set screws 86. The spring forces are of suiciently high values that operation of the platens cannot be obtained manually, and in the embodiment disclosed herein, movement of the platens to an open position for permitting insertion of a coil and sheet of insulation is obtained by providing a pair of stop pins 88 at the lower end of each side of the platens. These pins are engageable by a cam 90 having beveled ends 92. As is apparent, upward movement of the cam urges the pins and attached platens apart a distance suiicient to receive the coil C adapted for positioning therein. Downward movement of the coil in the device is limited by stop plates 94 oating between the bars. These plates extend through the faces of the platens and are loosely tted therein to permit their alignment in the event of misalignment between the platens. The cam is actuated to an upward position by an air actuated piston, as hereinafter described, and is returned to an inoperative position by a pair of springs 96 biased at their lower ends against an inner portion of the cam and at the upper ends against stops 98 provided on the drive plates 56. Limiting pins 100 limit the extent of movement of the cams in a vertical direction while gibs 101 guide the movement of the cams 90 vertically.

The apparatus used in driving the sprocket wheel 50 and attached platens consists of a motor 110 connected through a clutch 112 and brake 114 to a shaft 116 supported in bearings 118. A plurality of gear wheels 120 are mounted on the shaft for obtaining different driving speeds for the platens 26 and 28. In the embodiment shown, a drive chain is utilized for transmitting the power from the gear wheels 120 to the sprocket wheel 50 mounted in the right assembly on the table 20. As shown in Figure 2, firm engagement of the chain with the sprocket wheel is obtained by causing the chain to mesh with a pinion gear 122 supported by a bushing 124 and shaft 126 centrally mounted in the end plate 34 provided in the right assembly. In order to account for slack in the chain when a gear wheel of different size is used, an angle plate 123 is rigidly axed to the table and supports a disc 125 having a pair of oppositely disposed sprockets 127 over which the chain passes. The disc is further provided with openings 129 engageable by a lever arm 131 also pivoted on the table. As is apparent, when gear wheels of different size are used, the disc is rotated to either increase or decrease the length of chain passing over the sprockets 127 and the disc is rmly held against movement by virtue of the anchoring effect of the lever arm in openings 129. Obviously, other types of power sources and driving means may be employed, such as conventional belt drives or directly connected shafts, and varying speed of the platens may be obtained by using an adjustable speed motor, for example. Also, the drive plates in both assemblies may be driven concurrently, particularly in installations adapted for wrapping large size coils.

In operation, adhesive 130 is applied to opposite ends of a side of the sheet of insulation material I, such as Myler lm manufactured by E. l. du Pont de Nemours and Cornpany, or Irrathene irradiated polyethylene made by the General Electric Company, and one of such ends is attached to a side of the coil C to which it rigidly adheres. The coil is placed on stop member 94 between the open platens 26 and 28 and after insertion, the platens are caused to be moved to a closed position as illustrated in Figure 5. As the platens are rotated in a clockwise direction as viewed from the left in Figure 5, and shown in successive positions in Figures 6 through 9, the coil will tend to rotate with them, but a slight pressure exerted by an operator in an opposite direction. will cause the platens to move apart and compress springs therewithin. Upon reaching the position shown in Figure 9, the platens have been moved to their outermost position and the springs are fully compressed. As rotation continues with the coil held in the same position, the springs will permit the platens to move inwardly and outwardly while simultaneously wrapping the insulation I on the coil with a tight t. Upon completion of the process, the free end of the insulation with the adhesive coating is caused to adhere to the layer of insulation beneath it by virtue of the pressure exerted by the platens. In order to assure a tight fit, a layer of rubber R or other material is secured to a face of one of the platens to create a resisting force which is effective in tightly drawing the various layers against one another on the coil.

The structure described above obtains rotary movement of the platens, but their disposition for receiving or holding a coil, the number of revolutions made during the wrapping process and the adjustments necessary to properly position the platens at the end of each cycle is determined by a combined air and electrical circuit diagrammatically illustrated in Figure l0.

Referring now to Figures l and l0 for a general description and operation, the system shown includes controls for automatically opening and closing the wrapping platens, a D.C. supply for relays and electromagnetic clutch-brake actuation, a time delay unit for de-clutching and braking the rotating platens to a halt at a predetermined position so as to permit ready insertion and removal of a coil, and a pre-set counter utilized in automatically obtaining a predetermined member of insulation wraps on the coil.

Prior to initiating the wrapping procedure, air is applied to air cylinders 156 which urges the pistons 154 and plate into engagement with pins 88 thus maintaining the platens in an open or retracted position. Insertion of a coil with its attached sheet of insulation can then be made. With a counter set for a predetermined number of wraps, as hereinafter described, the wrapping sequence is commenced as follows: the motor is energized for continuous operation with rotary control of the platens 26 and 28 being accomplished by clutch 112 and brake 114. A D.C. voltage is supplied to the control circuits and in carrying out step 2, when foot switch 144, located in a position convenient for actuation by an operator, is depressed, theprimary, relay 146 is: energized/,thus closing a circuit through a cylinder relay 148 and a' control relay 150. In stepv 3, the cylinder relay 148 actuates air valve 152 which is eiective in retracting pistons 154 and associated cam plate 90 from its up position thereby `permitting platens 26 and 28 to move inwardly and grasp the coil C and the insulation previously attached thereto. The air valve is an ordinary type which when; energized, closes olir the supply of air to the aircylinders-1'56 while simultaneously venting them to thefatmosphere.l y j j In step 4, as the pistons are retracted, micro-switches 158 are closed thus completing a circuit through switch contacts previously closed by the control relay 150 to set a time delay relay 160 in step 5. The time delay relay is of conventional type in which the relay coil has a capacitor in parallel with it. The time delay cycle is initiated by removing the D.C. source of power from the relay coil and parallel capacitor combination. The discharging current of the capacitor keeps the relay coil energized and the relay contacts picked up. The time elapsed until the relay coil current decays to the point where the relay contacts drop out is a function of the size of the capacitor and resistance of the relay coil and the initial potential applied to the circuit.

In step 6, the clutch is energized and power is transmitted through the driving chain to sprocket wheel 52 which rotates the platens in a clockwise direction as viewed from the left in Figure l.

Step 7. As the platens rotate and wrap insulation on the coil, a microswitch 162 is contacted during each revolution thus transmitting a signal to a stepping relay 164 and preset circuit 166 which advances an arm one step each time it is pulsed by the microswitch. This step ping relay is of any well known design having a plurality of pins, each of which is adapted for contact by a lever manually movable to the pin corresponding to the desired number of wraps. A second lever or arm is advanced sequentially over the same pins by the relay until both levers contact the same pin, so that when the desired number or preset count is reached, the preset circuit, in step 8, transmits a signal to the timed elay device 160 which, in step 9, deenergizes the clutch and sets the brake on the motor shaft. The time delay is essential in the operation since it takes into account the time required for the platens to complete a partial revolution, that is, the time necessary for the platens to move to a horizontal position after the microswitch has been actuated. With the platens positioned horizontally, the coil can be readily removed.

ln steps and 11, the operator removes his foot from the foot switch to effect operation of the air valve which permits air under pressure to enter the air cylinders 156 and move the pistons upwardly into engagement with the cam plate 90 and actuate the platens to an open position. Because of the time delay device incorporated in the circuit, the platens assume a horizontal position thus permitting ready removal of the insulated coil. Opening of the foot switch also deenergizes the various circuits thus permitting the various contactors to assume a position ready for repetition of the above process.

It will be apparent that many modifications and varia tions are possible in light of the above teachings. For example, the time delay is made adjustable to allow the platens to stop in any one of a number of final positions to permit insertion and removal of a coil. The rate of platen opening can be made adjustable by merely adjusting a hand air valve in the air line. Different Wrapping speeds and types of drives can be resorted to, particularly where different size coils are wrapped by the machine. It therefore is to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.

What we claim as new and desire to secure by Letters Patent of the United States is:

1. A machine for wrapping insulation on coils for dynamoelectric machines, comprising a pair of frames mountingr a pair of movablysupported: platens; therebetween, at least one of. saidy framesv beingl adjustable'A relative to the other to permit use of platens of different size, means mounting said platens on bars rotatably mounted in said frames, meansV connected lwith saidplatens for selectively movingthem to open or closed positions, said last-namedv means comprising springs biasing` said platens toward: each other, Vaplurality of pins onsaid platens. en-

-gageableby a plate-.adjacent eachframe for moving said platens to an open position against the action of said springs to receive a coil and insulation adapted for wrapping thereon, an air actuated piston engageable with said plate to effect opening movement of said platens, a motor mechanically connected with said rotatably mounted bars in said frames and an electrically operable clutch and brake interposed between said motor and bars to obtain selective rotation of the latter, and an electrical counter responsive to each revolution of said platens connected in circuit with said clutch so that when said platens are rotated a predetermined number of times, said clutch is caused to be deenergized to stop rotation of said bars by said motor.

2. The combination according to claim 1 wherein an adjustable electrical time delay element is connected in circuit with said brake to permit adjustment of the stopping position of said bars so as to achieve a desired position for said platens.

3. A machine for applying insulation to coils for dynamoelectric machines comprising a pair of spaced frames movably mounted on a base to permit assumption of varying fixed positions relative to each other, a pair of bridging bars having their terminal ends fixed in means rotatably supported in said frames, a platen of U-shaped configuration movably mounted on each of said bars, biasing means located between said bars and said platens for urging the latter into a coil engaging position,control means engageable with said platens for selectively causing them to move to an open or closed position to respectively release or grasp said coil, a source of driving power perrnissively engageable with said means supported in one of said frames for effecting rotation of said platens used in wrapping insulation on said coil, and electrical means responsive to movement of said platens and connected in circuit with said driving means for controlling the number of revolutions of said platens and therefore the number of layers of insulation wrapped on said coil.

4. The combination according to claim 3 wherein said circuit further includes a time delay element for controlling the stopping position of said elements during the coil wrapping process.

5. A coil wrapping machine for wrapping insulation on coils for dynamoelectric machines comprising a pair of adjustable frames supporting a pair of rotatably mounted platens, means biasing said platens to a closed position, stop pins on said platens, an actuating plate positioned adjacent said platens and selectively movable into engagement with said pins for moving said platens to an open coil yreceiving position, a source of driving power connected with said platens, selectively operable clutch means interposed therebetween to obtain selective rotation of the platens, an electrical circuit responsive to each revolution made by said platens and being connected with said operable means to de-energize the latter after a predetermined number of revolutions have been made by said platens which determines the number of layers of insulation on said coil.

6. A coil wrapping machine for applying insulation to la coil used in a dynamoelectric machine comprising a pair of spaced frames, means in said frames supporting a pair of bridging bars having their terminal ends rotatably mounted therein, a slidably mounted platen on each of said bars biased toward each other by means interconnecting the bars with the platens, stop members on each of said platens, an actuating device mounted adjacent Said bars and connectedv with a power source so that upon application of power to said actuating device, the latter is caused to move into engagement with said stop members for urging said platens against the action of said biasing means away from each other to a coil receiving position, power driving means permissively engageable with said bars for eecting rotation of said platens, an electrical counter connected with said bars for counting the number of revolutions of said platens, and a timing device in for stopping rotation of nid platens after a predetermined period of time.

References Cited in the le of this patent circuit with said counter and said power driving means 10 2,726,817

UNITED STATES PATENTS Haefely Mar. 17, 1914 Haefely Dec. 15, 1914 Dicks et al; Nov. 12, 1918 Snyder Feb. 13, 1934 Barrows Dec. 13, 1955 

